---
title: Charmhub | Deploy Cassandra using Charmhub - The Open Operator Collection
description: Deploy the latest version of Cassandra on any cloud.
url: https://charmhub.io/cassandra/configurations
---

# Cassandra

[Canonical Data Platform](https://charmhub.io/publisher/dataplatformbot "View all packages from Canonical Data Platform")

* [Canonical Data Platform](https://charmhub.io/publisher/dataplatformbot "View all packages from Canonical Data Platform")
* [Databases](https://charmhub.io/?filter=databases)

Platform:

24.04

20.04

18.04

16.04

14.04

stable cs-cassandra-54-21-g00dc91e-dirty

```
juju deploy cassandra
```

[Learn to deploy on juju >](https://juju.is/docs/juju/manage-applications)

* [authenticator](https://charmhub.io/cassandra/configurations#authenticator)
* [authorizer](https://charmhub.io/cassandra/configurations#authorizer)
* [cluster\_name](https://charmhub.io/cassandra/configurations#cluster_name)
* [commitlog\_directory](https://charmhub.io/cassandra/configurations#commitlog_directory)
* [compaction\_throughput\_mb\_per\_sec](https://charmhub.io/cassandra/configurations#compaction_throughput_mb_per_sec)
* [cron\_maintenance](https://charmhub.io/cassandra/configurations#cron_maintenance)
* [data\_file\_directories](https://charmhub.io/cassandra/configurations#data_file_directories)
* [datacenter](https://charmhub.io/cassandra/configurations#datacenter)
* [dse\_version](https://charmhub.io/cassandra/configurations#dse_version)
* [edition](https://charmhub.io/cassandra/configurations#edition)
* [external\_seeds](https://charmhub.io/cassandra/configurations#external_seeds)
* [external\_superuser\_password](https://charmhub.io/cassandra/configurations#external_superuser_password)
* [external\_superuser\_username](https://charmhub.io/cassandra/configurations#external_superuser_username)
* [extra\_packages](https://charmhub.io/cassandra/configurations#extra_packages)
* [file\_cache\_size\_in\_mb](https://charmhub.io/cassandra/configurations#file_cache_size_in_mb)
* [heap\_newsize](https://charmhub.io/cassandra/configurations#heap_newsize)
* [http\_proxy](https://charmhub.io/cassandra/configurations#http_proxy)
* [install\_keys](https://charmhub.io/cassandra/configurations#install_keys)
* [install\_sources](https://charmhub.io/cassandra/configurations#install_sources)
* [io\_scheduler](https://charmhub.io/cassandra/configurations#io_scheduler)
* [jre](https://charmhub.io/cassandra/configurations#jre)
* [listen\_interface](https://charmhub.io/cassandra/configurations#listen_interface)
* [max\_heap\_size](https://charmhub.io/cassandra/configurations#max_heap_size)
* [nagios\_context](https://charmhub.io/cassandra/configurations#nagios_context)
* [nagios\_disk\_crit\_pct](https://charmhub.io/cassandra/configurations#nagios_disk_crit_pct)
* [nagios\_disk\_warn\_pct](https://charmhub.io/cassandra/configurations#nagios_disk_warn_pct)
* [nagios\_heapchk\_crit\_pct](https://charmhub.io/cassandra/configurations#nagios_heapchk_crit_pct)
* [nagios\_heapchk\_warn\_pct](https://charmhub.io/cassandra/configurations#nagios_heapchk_warn_pct)
* [nagios\_servicegroups](https://charmhub.io/cassandra/configurations#nagios_servicegroups)
* [native\_transport\_port](https://charmhub.io/cassandra/configurations#native_transport_port)
* [num\_tokens](https://charmhub.io/cassandra/configurations#num_tokens)
* [package\_status](https://charmhub.io/cassandra/configurations#package_status)
* [partitioner](https://charmhub.io/cassandra/configurations#partitioner)
* [private\_jre\_url](https://charmhub.io/cassandra/configurations#private_jre_url)
* [rack](https://charmhub.io/cassandra/configurations#rack)
* [repair\_maintenance\_args](https://charmhub.io/cassandra/configurations#repair_maintenance_args)
* [rpc\_interface](https://charmhub.io/cassandra/configurations#rpc_interface)
* [rpc\_port](https://charmhub.io/cassandra/configurations#rpc_port)
* [saved\_caches\_directory](https://charmhub.io/cassandra/configurations#saved_caches_directory)
* [snapd\_refresh](https://charmhub.io/cassandra/configurations#snapd_refresh)
* [ssl\_storage\_port](https://charmhub.io/cassandra/configurations#ssl_storage_port)
* [storage\_port](https://charmhub.io/cassandra/configurations#storage_port)
* [stream\_throughput\_outbound\_megabits\_per\_sec](https://charmhub.io/cassandra/configurations#stream_throughput_outbound_megabits_per_sec)
* [tombstone\_failure\_threshold](https://charmhub.io/cassandra/configurations#tombstone_failure_threshold)
* [tombstone\_warn\_threshold](https://charmhub.io/cassandra/configurations#tombstone_warn_threshold)
* [wait\_for\_storage\_broker](https://charmhub.io/cassandra/configurations#wait_for_storage_broker)

[Learn about configurations >](https://juju.is/docs/juju/configuration#heading--application-configuration)

* authenticator | string

  Default: PasswordAuthenticator

  Authentication backend. Only PasswordAuthenticator and AllowAllAuthenticator are supported. You should only use AllowAllAuthenticator for legacy applications that cannot provide authentication credentials.
* authorizer | string

  Default: AllowAllAuthorizer

  Authorization backend, implementing IAuthorizer; used to limit access/provide permissions Out of the box, Cassandra provides AllowAllAuthorizer & CassandraAuthorizer - AllowAllAuthorizer allows any action to any user - set it to
  disable authorization.

  + CassandraAuthorizer stores permissions in
    system\_auth.permissions table.
* cluster\_name | string

  Default: juju

  Name of the Cassandra cluster. This is mainly used to prevent machines in one logical cluster from joining another. All Cassandra services you wish to cluster together must have the same cluster\_name. This setting cannot be changed after service deployment.
* commitlog\_directory | string

  Default: commitlog

  Commit log directory. The path is relative to /var/lib/cassandra or the block storage broker external mount point.
* compaction\_throughput\_mb\_per\_sec | int

  Default: 16

  Throttles compaction to the given total throughput (in MB/sec) across the entire system. The faster you insert data, the faster you need to compact in order to keep the sstable count down, but in general, setting this to 16 to 32 times the rate you are inserting data is more than sufficient. Setting this to 0 disables throttling. Note that this account for all types of compaction, including validation compaction.
* cron\_maintenance | boolean

  Node needs to be repaired regularly so that the consistency of the data is maintained. The old version of cassandra was assuming a single application that would spread a full repair over the course of the week. This is not how this is done anymore and this config is there to deactivate this maintenance when needed.
* data\_file\_directories | string

  Default: data

  Space delimited data directories. Use multiple data directories to split data over multiple physical hardware drive partitions. Paths are relative to /var/lib/cassandra or the block storage broker external mount point.
* datacenter | string

  Default: juju

  The node's datacenter used by the endpoint\_snitch. e.g. "DC1". It cannot be changed after service deployment.
* dse\_version | string

  Default: 6.0

  The major DataStax Enterprise version to track when edition is set to 'dse'. One of "4.7", "4.8", "5.0", "5.1", "6.0".
* edition | string

  Default: community

  One of 'community', 'dse', or 'apache-snap'. 'community' uses the Apache Cassandra packages. 'dse' is for DataStax Enterprise. Selecting 'dse' overrides the jvm setting. 'apache-snap' uses a snap package of Apache Cassandra.
* external\_seeds | string

  Space separated list of gossip seed IP addresses used to join an existing external cluster. If unset, the charm will operate in managed mode and create a new cluster.
* external\_superuser\_password | string

  Superuser password for the existing cluster. Must be set if and only if external\_seeds is.
* external\_superuser\_username | string

  Superuser username for the existing cluster. Must be set if and only if external\_seeds is.
* extra\_packages | string

  Space separated list of extra deb packages to install.
* file\_cache\_size\_in\_mb | int

  Maximum memory to use for sstable chunk cache and buffer pooling. 32MB of this are reserved for pooling buffers, the rest is used as an cache that holds uncompressed sstable chunks. Defaults to the smaller of 1/4 of heap or 512MB. This pool is allocated off-heap, so is in addition to the memory allocated for heap. The cache also has on-heap overhead which is roughly 128 bytes per chunk (i.e. 0.2% of the reserved size if the default 64k chunk size is used). Memory is only allocated when needed.
* heap\_newsize | string

  Default: 32M

  The size of the JVM's young generation in the heap. If you set this, you should also set max\_heap\_size. If in doubt, go with 100M per physical CPU core. The default is automatically tuned.
* http\_proxy | string

  DEPRECATED. Use Juju model-config settings. Value for the http\_proxy and https\_proxy environment variables. This causes pip(1) and other tools to perform downloads via the proxy server. eg. http://squid.dc1.lan:8080
* install\_keys | string

  Default: - null # Apache and DataStax package signing keys are added automatically.

  List of signing keys for install\_sources package sources, per charmhelpers standard format (a yaml list of strings encoded as a string). The keys should be the full ASCII armoured GPG public keys. While GPG key ids are also supported and looked up on a keyserver, operators should be aware that this mechanism is insecure. null can be used if a standard package signing key is used that will already be installed on the machine, and for PPA sources where the package signing key is securely retrieved from Launchpad.
* install\_sources | string

  Default: - deb http://www.apache.org/dist/cassandra/debian 311x main

  charm-helpers standard listing of package install sources. If you are using Datastax Enterprise, you will need to override one defaults with your own username and password.
* io\_scheduler | string

  Default: noop

  Set kernel io scheduler for persistent storage. https://www.kernel.org/doc/Documentation/block/switching-sched.txt
* jre | string

  Default: openjdk

  Which Java runtime environment to use. May be 'openjdk' or 'oracle'.
* listen\_interface | string

  Network interface used for connecting to other Cassandra nodes. Must correspond to a single IP address. By default, the unit's public IP address is used.
* max\_heap\_size | string

  Default: 384M

  Total size of Java memory heap, for example 1G or 512M. If you set this, you should also set heap\_newsize. The default is automatically tuned.
* nagios\_context | string

  Default: juju

  Used by the nrpe subordinate charms.
  A string that will be prepended to instance name to set the host name
  in nagios. So for instance the hostname would be something like:
  juju-myservice-0
  If you're running multiple environments with the same services in them
  this allows you to differentiate between them.
* nagios\_disk\_crit\_pct | int

  Default: 25

  The pct of data disk used to trigger a nagios critcal alert
* nagios\_disk\_warn\_pct | int

  Default: 50

  The pct of data disk used to trigger a nagios warning
* nagios\_heapchk\_crit\_pct | int

  Default: 90

  The pct of heap used to trigger a nagios critcal alert
* nagios\_heapchk\_warn\_pct | int

  Default: 80

  The pct of heap used to trigger a nagios warning
* nagios\_servicegroups | string

  A comma-separated list of nagios servicegroups.
  If left empty, the nagios\_context will be used as the servicegroup
* native\_transport\_port | int

  Default: 9042

  Native protocol port for native protocol clients.
* num\_tokens | int

  Default: 256

  Number of tokens per node.
* package\_status | string

  Default: install

  The status of service-affecting packages will be set to this value in the dpkg database. Valid values are "install" and "hold".
* partitioner | string

  Default: Murmur3Partitioner

  The cassandra partitioner to use. Use Murmur3Partitioner, unless another is required for backwards compatibility.
* private\_jre\_url | string

  URL for the private jre tar file. DSE requires Oracle Java SE 8 Server JRE (eg. server-jre-8u60-linux-x64.tar.gz).
* rack | string

  The rack used by the endpoint\_snitch for all units in this service. e.g. "Rack1". This cannot be changed after deployment. It defaults to the service name. Cassandra will store replicated data in different racks whenever possible.
* repair\_maintenance\_args | string

  Node repair arguments. By default, the command is run locally as `nodetool repair`. Any part of this string will be added to this command in the cron maintenance call. This parameter is ignored if `cron_maintenance` is set to False.
* rpc\_interface | string

  Network interface used for client connections. Must correspond to a single IP address. By default, the unit's public IP address is used.
* rpc\_port | int

  Default: 9160

  DEPRECATED, ignored by Cassandra 3.11+. Thrift protocol port for legacy clients.
* saved\_caches\_directory | string

  Default: saved\_caches

  Saved caches directory. The path is relative to /var/lib/cassandra or the block storage broker external mount point.
* snapd\_refresh | string

  How often snapd handles updates for installed snaps. The default (an empty string) is 4x per day. Set to "max" to check once per month based on the charm deployment date. You may also set a custom string as described in the 'refresh.timer' section here:
  https://forum.snapcraft.io/t/system-options/87
* ssl\_storage\_port | int

  Default: 7001

  Cluster secure communication port. TODO: Unused. configure SSL.
* storage\_port | int

  Default: 7000

  Cluster communication port
* stream\_throughput\_outbound\_megabits\_per\_sec | int

  Default: 200

  Throttles all outbound streaming file transfers on nodes to the given total throughput in Mbps. This is necessary because Cassandra does mostly sequential IO when streaming data during bootstrap or repair, which can lead to saturating the network connection and degrading rpc performance. When unset, the default is 200 Mbps or 25 MB/s. 0 to disable throttling.
* tombstone\_failure\_threshold | int

  Default: 100000

  When executing a scan, within or across a partition, we need to keep the tombstones seen in memory so we can return them to the coordinator, which will use them to make sure other replicas also know about the deleted rows. With workloads that generate a lot of tombstones, this can cause performance problems and even exaust the server heap. Adjust the thresholds here if you understand the dangers and want to scan more tombstones anyway.
* tombstone\_warn\_threshold | int

  Default: 1000

  When executing a scan, within or across a partition, we need to keep the tombstones seen in memory so we can return them to the coordinator, which will use them to make sure other replicas also know about the deleted rows. With workloads that generate a lot of tombstones, this can cause performance problems and even exaust the server heap. Adjust the thresholds here if you understand the dangers and want to scan more tombstones anyway.
* wait\_for\_storage\_broker | boolean

  Do not start the service before external storage has been mounted using the block storage broker relation. If you do not set this and you relate the service to the storage broker, then your service will have started up using local disk, and later torn down and rebuilt when the external storage became available.
